Derrick structure and method for raising a derrick mast



:March 6, 1934.-

G. R. LUNT El AL DERRICK STRUCTURE AND METHOD FOR RAISING DERRICK MASTFiled Jan. 11, 1932 2 Sheets-Sheet l @EEELCZJ HQBQO R U ET AL L94fi$DERRICK STRUfiTURE AND METHOD FOR RAISING A DERRICK MAST Filed Jan. 11,1932 2 Sheets-Sheet Patented Mar. 6, 1934 DERRICK STRUCTURE AND IVIETHODFOR RAISING A DERRICK MAST Gordon R. Lunt and Cedric Fegtly, Des Moines,Iowa, assignors to Pittsburgh Des Moines Steel Company, Des Moines,Iowa, a corporation Application January 11, 1932, Serial No. 586,062

9 Claims.

Our invention relates to a derrick structure and to a method for raisingthe mast thereof.

It is the purpose of our invention to provide a derrick structure,particularly adapted for quickly, inexpensively and easily raising themast thereof, after it has been assembled in a horizontal positionadjacent the location where it is to be erected.

Another purpose is to provide a simple method whereby a derrick mast.may be quickly and easily raised in a short time with a minimum oflabor.

With these and other objects in view our invention consists in theconstruction, arrangement and combination of the various parts of ourdevice, whereby the objects contemplated are attained, as hereinaftermore fully set forth,

pointed out in our claims, and illustrated in the accompanying drawings,in which:

Figure l is a diagrammatic side elevation of a derrick structure showingit in one position during the starting stages of the derrick mast raising operation which is carried on according to our method.

Figure 2 is a sectional view on the line 2-2 of Figure 1 showing aposition retaining means.

Figure 3 is a diagrammatic side elevation showing further stages in thederrick mast raising operation.

Figure 4 is a side elevation'of the derrick in erected position.

Figure 5 is a rear elevation of the lower end of the derrick mastshowing cribbing and jacks supporting the mast.

Figure 6 is a plan view of the same on the line 66 of Figure 5.

Figure '7 is a side elevation of Figure 5; and

Figure 8 'is a similar side elevation showing a slightly difierentmethod for finally setting the derrick mast in position.

' On the accompanying drawings, we have used the reference character Ato indicate a derrick mast and the reference character B to indicate aderrick boom. The mast and boom are of any suitable kind, preferablyfabricated of steel.

The mast A has at its lower end a mast base 10 adapted to fitiin aderrick base 12 when the derrickis in erected position. Bed pieces 13 orany suitable foundation are usually provided for the derrick base 12.The derrick base itself usually has brackets 15 supporting cable sheaves17 under which the various cables for operating the derrick extend. Thisis all part of the derrick construction and does not need to be furtherdescribed.

The boom B is comprised of boom sections or members 14, 16 and 18. Theboom member 14 is pivoted by means of a pin 20 to gusset plates 22 whichare secured to the lower end of the mast A.

.In the practice of our method, the ordinary derrick construction thusfar described is modifled as will now be described. Gusset plates 24 aresecured to the lower end of the mast A and extend (relative to the axisof the mast) in an opposite direction from the gusset plates 22. Thegusset plates 24 are provided with openings 26 to receive a pivot orcross shaft 28 which may be an extra heavy pipe or the like. Cribbing30, 32, 34, 36 and 38 as well as jacks 40, trunnions 42, blocks 44 andshims 46 are used in conjunction with the pivot shaft 28, in conectionwith the practice of our method.

Also in the practiceof our method a hoist or winch 48 is used havingcable drums 50 and 52 for cables 54 and 56, respectively.

The cable 54 is connected with the boom member 14 and the cable 56extends through pulley blocks 58 and 60. The pulley block 58 isconnected with a cable 62, while the pulley block 60 is connected with adead man or anchor 64. A cable 55 is provided for limiting the boommember 14 and the mast A to a predetermined angular position withrelation to each other.

The cable 62 is preferably doubled-that is, it has one end secured tothe mast A, as for instance to an ear 66 thereon, with the intermediatepart of the cable extending to the pulley block 58 and then back againand with its other end secured to the mast A. The intermediate part ofthe cable 62 extends over the upper end of the boom member 14, as shownin Figure 1 by full lines, it merely contacting with the upper endthereof, A short metal bar 68 may be secured to each side ofthe boommember 14 to prevent the cable 62 from sliding sidewise ofi the end ofthe boom member.

Guy cables 70, '72 and '14 for the mast A are provided in the ordinarymanner, these being connected with a spider 76 at the upper end of themast and being adapted for connection with dead men '78, 80 and 82,respectively. The guy cables 70 extend sidewise from the mast, the guycable 72 extends rearwardly therefrom and the guy cable '74 extendsforwardly therefrom.

During the raising operation for' the mast, block and tackle take-updevices 84 are preferably interposed between the dead men 78 and the guycables 70; y

In connection with our raising method we further provide a positionretaining cable 86 having its ends connected with the pivot shaft 28 andits intermediate portion with a dead man 88. Turn buckles orotherItake-up devices are interposed in the length of the cable 86 foradjustment purposes.

Description of method for raising the derrick mast Having described a,derrick structure with modifications which adapt it for our method, we

will now describe the method itself step by step. (1) The bed pieces 13are accurately located and leveled and the derrick base 12 is supportedthereon in final desired position.

(2) Dead men or anchors '78, 80, 82 and 88 are all located, with thedead man 88 directly .under the position from which the mast is to beraised. If soil conditions require it, two dead men 88 may be usedinstead of the single one. When two are used, they are located onopposite sides of the mast about four or five feet apart.

(3) The mast A is assembled on the ground as near as possible to theposition from which it is to be raised.

(4) With the pivot shaft 28 in place, the base of the mast A is jackedipor otherwise raised until the shaft 28 is in the proper relativeposition to the derrick base 12.

(5) The cribbing 30, 32, 34, 36 and 38 together with the shims 46 arethen placed in po 'sition and the blocks 44 nailed on the cribbing 38 topositively position the shaft 28 nally of the cribbing 38.

Thereafter the jacks are removed and the mast is leveled to thehorizontal position shown in Figure 1 by raising the upper end of themast and by the use of cribbing 92.

(6) The position retaining cable 86 is then placed in position forholding the shaft 28 against displacement, the turn buckles 90 beingtightened to draw the cable 86 substantially taut.

('7) The guy cables '70, '72 and '74 are then secured to the spider '76and to the dead men '78 and 80.

(8) The boom member 14 is then pinned in position, it restinghorizontally on the mast A as shown by dotted lines in Figure 1.

(9) The cable 62 is then assembled in the dotted line position of Figure1, the cables 54, 55 and 56 also being assembled in their dotted lineposition. The bars 68 are secured in position on the upper end of theboom member 14.

(10) The cable 54 is then wound in to raise the boom member 14 from itshorizontal dotted position to its vertical full line position ofFigure 1. The cable 55 is of the proper length to limit the anglebetween the boom member and the mast to substantially a right angle.

(11) The cable 56 is then wound on the drum 52 to first tighten thecable 62 and then start swinging the mast and the boom about the pivotshaft 28, as for instance to the solid line position of Figure 3, thedrum 50 during the raising operation being manipulated to keep the slackout of the cable 54. 1

Soon a ter the position of Figure 3 is reached the cable 62 will ceasecontacting with the outer end of the boom member 14 and pull directly onthe mast A as shown by dotted lines in Figure 3. This arrangementprovides for proper leverage of the raising cable 56 on the mast A, bothwhile it is in its horizontal position and while it is adjacent itsvertical position. During the raising operation, the block and tackledevices 84 longitudi- I aremanually manipulated to keep the side guycables 70 taut to prevent any side toppling of the mast A. a

' (12) When the mast finally assumes its vertical position as shown inFigure 4, the jacks 40 are positioned on the cribbing 33 and support thetrunnions 42 under the pivot shaft 28. The jacks may then be manipulatedfor raising the shaft off the cribbing 38, whereafter the shims 46successively may be removed as the jacks are lowered for lowering themast base 10 into the derrick base 12.

In some instances, especially on light derricks, the jacks 40 andtrunnions 42 may be dispensed with as shown in Figure 8, the cribbing 38being arranged low enough to allow the mast base 10 to roll into seatingengagement with the derrick base 12 during the final portion of theraising of the derrick mast which raises the shaft 28'from the cribbing38 as illustrated. Thereafter the shims and cribbing may be removedwithout the necessity of having to use jacks for releasing the cribbingand lowering. the derrick mast.

The process of lowering the mast is just the reverse of the raisingprocess.

From the foregoing description it will be seen, that we have provided amethod for raising a derrick mast which involves far less work and feweroperations and thus facilitates the raising of the derrick mast. Onesection of the boom is effectively used during the raising operation forproviding the proper leverage to raise the mast from its horizontalposition. Our method entirely eliminates the erection of a smalltemporary mast to be used for then erecting the larger permanent mast.The method just mentioned is the one now in common use.

Some changes in our means for supporting the pivot shaft on the derrickmast and changes in the steps of the method for raising the mast may bemade without departing from the real spirit and purpose of ourinvention, and it is our intention to cover by our claims, any modifiedforms of structure or use of mechanical equivalents, which may bereasonably included within their scope.

We claim as our inven'ion:

1. In a structure of the kind described, a mast, a lower boom sectionpivoted to the lower end thereof, an upper boom section beingsubsequently attachable to said lower boom section to form an extensionthereof whereby the two form a boom of substantial length, means forfixing the mast and lower boom section in predetermined angular relationto each other, a cross shaft associated with the lower end of the mast,means for supporting the cross shaft and a cable connected with the mastand engaging the end of the boom member whereby pull on the cable movesthe boom member and the mast around the axis of the cross shaft forraising the mast and the cable can leave the end of the boom memberduring the latter part of the raising movement.

2; In a structure of the kind described, a mast, a lower boom sectionpivoted to the lower end thereof, an upper boom section beingsubsequentouter end of said lower boom section, means for eaarsopivotally mounting the lower end of said mast, said raising cablecontacting only with said outer end of said lower boom section-wherebypulling on said raising cable will swing said section and said mastaround the pivotal mounting for said mast and in so doing, will leavesaid outer end of said lower boom section.

3. The method of erecting a derrick comprising pivoting a lower boomsection to the lower end of a mast, supporting the lower end of the mastby means of a cross shaft with the mast lying substantially horizontal,raising the lower boom section, fixing the mast and the lower boomsection in predetermined angular relation to each other and pulling acable associated with the lower boom section from a position spaced fromthe lower boom section in a direction opposite the mast to rock the boommember and the mast on a common pivot for raising the same.

4. The method of raising a derrick comprising pivoting a lower boomsection to the lower end of a derrick mast, fixing a cable to the mastand to the lower boom section at points spaced from the pivot of thelower boom section' to the mast, raising the lower boom section untilsaid cable is taut, imparting pivotal movement to the lower boom sectionand the mast for raising the mast to vertical position and attaching anupper boom sectionto said lower boom section as a continuation thereof.5. The method of raising a derrick comprising pivoting the lower boomsection to the lower end of a derrick mast, fixing a cable to the mastand to the lower boom section away from the pivot of the lower boomsection to the mast to limit their relative movement to 'a predeterminedangular relationship, providing a common pivot for the lower boomsection and the mast, imparting movement to the lower boom section andthe mast to rock them around said common pivot for raising the mast tovertical position, attaching an upper boom section to said lower boomsection whereby the lower and upper boom sections constitute a derrickboom and raising said derrick boom to operating position.

6. The method of raising a derrick comprising pivoting a lower boommember to the lower end of a derrick boom mast, fixing a cable to themast and to the lower boom section spaced from the pivot of one to theother to limit their relative movement to a predetermined angularrelation, providing a common pivot for the lower boom section and themast, fixing a second cable to said mast intermediate its ends,extending the 1 second cable over the outer end of the lower boomsection and pulling on said second cable to rock said lower boom sectionand said mast around said commonpivot and tocause said second cable toleave said lower boom sectionfor vthe purpose of raising the mast.

7. The method of raising a derrick from hori= zontal position comprisingpivoting a lower boom section to the lower end of a mast, connecting aposition retaining cable with the lower end of the mast, raising thelower boom section, limiting the angular relationof. the lower boomsection to the mast and pulling a cable associated by contact with theouter end of the boom member and by connection with the mast, from aposition spaced from the lower boom section in a direction opposite themast for swinging the lower boom section and the mast around a commonpivot and thereby raising the mast to vertical position, lowering thelower boom section to horizontal position, fastening an extension on thelower boom section and raising the lower a boom section and itsextension to serve as a derrick boom.

8. In a structure of the kind described, a mast, a lower boom sectionpivoted to the lower end thereof on one side of the lengthwise axis ofthe mast, an upper boom section being subsequently attachable to theouter end of said lower boom section, a pivotal support for the lowerend of said mast on the other side of said axis, a cable fixed to themast and to the lower boom section at points spaced from the firstmentioned pivot for limiting the angular movement lower boom section andthe mast, means including a cable contacting only with the outer end .ofthe lower boom section and disengageable therefrom during the raising ofthe mast, whereby the lower boom section and the mast may be rockedabout the second mentioned pivot for raising the mast and a scatter thelower end of the mast to engage in upon its assumption of such raisedposition. i i

9. In a structure of the kind described, a mast, a lower boom sectionpivoted to the lower end of said mast on one side of the lengthwise axisthereof, an upper boom section being subsequently attachable to theouter end of said lower boom section, a pivotal support for the lowerend of said -cable on the other side of said axis, means for fixing theposition of said pivotal support to retain it in a. desired positionduring raising of said mast, a cable fixed to the mast and to the lowerboom section at points spaced from said first mentioned pivot forlimiting its angular movement apart from said lower boom section andsaid mast, means including a cable engageable with and disengageablefrom the outer end of said lower boom section for rocking the boommember and the member about the second mentioned pivot'for raising themast and a seat for assumption of such'raised position.

GORDON R. LUNT. CEDRIC FEG'ILY.

apart of the

